Project summary/abstract TB is the leading cause of death among persons with HIV worldwide, and HIV-infected drinkers are at very high risk for TB disease and mortality; receipt of six months of isoniazid (INH) preventive therapy (IPT) reduces TB morbidity and mortality by 30-50% above the benefit of antiretroviral therapy (ART), however, INH can be toxic to the liver. Thus, interventions to reduce alcohol use are needed to decrease INH toxicity during IPT among HIV/TB infected drinkers. It is also well established that heavy drinkers have poorer ART adherence, and there is growing evidence of reduced IPT adherence in drinkers. However, interventions to reduce drinking have had limited impact on ART adherence, and further interventions to increase IPT adherence among HIV/TB infected drinkers are likely needed. The use of incentives to promote healthy behavior is a highly effective approach for reducing substance use and for improving adherence to HIV and TB regimens in resource-rich settings. Economic incentives to reduce alcohol use may create a window for safe and effective IPT use over six months by decreasing hepatotoxicity. Decreases in alcohol use may also improve IPT adherence, or additional incentives for IPT adherence may be needed. Such strategies to reduce alcohol use have not been studied in low-income countries and the effectiveness of incentives to optimize IPT in HIV/TB co-infected drinkers is unknown. The DIPT Study is a factorial design randomized controlled trial that aims to test interventions for reduced drinking and increased medication adherence to safely and effectively provide tuberculosis (TB) preventive therapy to HIV/TB co-infected drinkers in sub-Saharan Africa. The study utilizes behavioral theory to provide economic incentives for reduced drinking and isoniazid (INH) adherence measured by point-of-care tests. The study outcomes are (1) reduced heavy drinking during the 6-months of INH, (2) increased isoniazid (INH; the drug used to prevent active TB) pill taking, and (3) increased viral suppression over 12 months, in the intervention arms compared to the control. As far as we are aware, this is the first study to examine the use of economic incentives to reduce alcohol use and to increase medication adherence in HIV-infected drinkers in sub-Saharan Africa, so the findings from this study will be seminal. The DIPT Study will collect outcome data, including objective biologic measures of alcohol use, INH adherence, and HIV viral suppression, and quantitative data on potential mediators and moderators of the effects; there is no current budget for qualitative data collection. Therefore, we propose a qualitative study with a subset of DIPT participants in order to deepen our understanding of how economic incentives for decreased drinking and increased INH adherence among HIV/TB co-infected drinkers are perceived to impact these outcomes, and their collateral effects on HIV risk taking, interpersonal relationships and violence, and economic well-being.